power ISUZU TF SERIES 2004 Workshop Manual

6E-148 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
8
Using the DVM and check the MAF sensor signal
circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the MAF sensor connector.
3. Ignition "On".
4. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
V

E-63


Less than 1V
Go to Step 9
Repair faulty
harness and
verify repair
9
Check any accessory parts which may cause electric
interference.
- Remove the
accessory parts
and verify repair
Go to Step 10
10
Check the shield wire for open or short circuit.
Was the problem found?
- Verify repair Go to Step 11
11
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 12 Go to Step 13
12
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair
13
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 14
14
Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual. Following
ECM programming, the immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement” for the
ECM/Immobilizer linking procedure.
- Verify repair -

6E-152 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No

Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the MAF sensor connector and ECM
connector.
3. Check the circuit for open, short to sensor ground
or short to ground circuit.
Was the problem found?
E-61(B)




E-63





- Repair faulty
harness and
verify repair Go to Step 7
7
Using the DVM and check the MAF sensor power
supply circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the MAF sensor connector and ECM
main relay.
3. Check the circuit for open circuit.
Was the problem found?


X-13E-63





-
Repair faulty
harness and
verify repair
Go to Step 8
8
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 9 Go to Step 10
9
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair -
10
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 11

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-157
Step Action Value (s) Yes No
7
Using the DVM and check the MAF sensor ground
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the MAF sensor connector .
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-63
V




Less than 1V
Go to Step 8
Repair faulty
harness and
verify repair
8
Using the DVM and check the MAF sensor signal
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the MAF sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-63
V




Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair
9
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 10 Go to Step 11
10
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair -
11
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 12
12
Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual. Following
ECM programming, the immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement” for the
ECM/Immobilizer linking procedure.
- Verify repair -

6E-166 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9
Repair the short to voltage circuit between the ECM
and IAT sensor.
Was the problem solved?
E-60(A)
E-63




- Verify repair Go to Step 14
10
Using the DVM and check the IAT sensor ground
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the IAT sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-63
V




Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair
11
Using the DVM and check the IAT sensor ground
circuit.
Breaker box is available:
1. Ignition "Off", engine "Off".
2. Install the breaker box as type A (ECM
disconnected).
Refer to 6E-95 page.
3. Disconnect the IAT sensor connector.
4. Check the circuit for open circuit.
Was the problem found?
B39
Breaker Box
E-63

6E-176 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9
Repair the short to voltage circuit between the ECM
and ECT sensor.
Was the problem solved?
E-60(A)
E-69




- Verify repair Go to Step 14
10
Using the DVM and check the ECT sensor ground
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the ECT sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-69
V




Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-181
Step Action Value (s) Yes No
6
Check for the following conditions.

Objects blocking the throttle valve.

Vacuum leaking at throttle body.
If a problem is found, repair as necessary.
Was the problem found?
- Verify repair Go to Step 7
7
Check for poor/faulty connection at the TPS or ECM
connector. If a poor/faulty connection is found, repair
the faulty terminal.
Was the problem found?
E-61(B)




E-68




- Verify repair Go to Step 8
8
Visually check the TPS.
Was the problem found?
- Go to Step 12 Go to Step 9
9
Using the DVM and check the TPS signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the TPS connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-68


V


Less than 1V
Go to Step 10
Repair faulty
harness and
verify repair
10
Check any accessory parts which may cause electric
interference.
Was the problem found?
- Remove the
accessory parts
and verify repair Go to Step 11
11
Check the shield wire for open or short circuit.
Was the problem found?
- Verify repair Go to Step 12
12
Substitute a known good TPS and recheck.
Was the problem solved?
- Go to Step 13 Go to Step 14
13
Replace the TPS.
Is the action complete?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-185
Step Action Value (s) Yes No
6
Using the DVM and check the TPS.
1. Ignition "Off", engine "Off".
2. Disconnect TPS connector.
3. Measure the resistance of TPS.
Does the tester indicate standard resistance as shown
in the following table?
TPS










Measurement Terminal Resistance (

) 1 - 2 Approximately 4.7k

at idle position Approximately 1.0k

at WOT 2 – 3 Approximately 0.6k

at idle position Approximately 4.3k

at WOT
1 – 3 Approximately 5.0k

at idle position & WOT

Standard
resistance
Go to Step 7
Go to Step 10
7
Using the DVM and check the TPS power supply
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the TPS connector.
3. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
E-68


V


Approximately
5.0V
Go to Step 9
Go to Step 8
8
Repair the open or short to ground circuit between the
ECM and TPS.
Was the problem solved?
E-68


E-61(B)

- Verify repair Go to Step 12

6E-190 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
6
Using the DVM and check the TPS.
1. Ignition "Off", engine "Off".
2. Disconnect TPS connector.
3. Measure the resistance of TPS.
Does the tester indicate standard resistance as shown
in the following table?
TPS










Measurement Terminal Resistance ()
1 - 2 Approximately 4.7k at idle position
Approximately 1.0k at WOT
2 – 3 Approximately 0.6k at idle position
Approximately 4.3k at WOT
1 – 3 Approximately 5.0k at idle position & WOT
Standard
resistance
Go to Step 7
Go to Step 12
7
Using the DVM and check the TPS power supply
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the TPS connector.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated specified value?
E-68


V


Approximately
5.0V
Go to Step 9
Go to Step 8
8
Repair the short to voltage circuit between the ECM
and TPS.
Was the problem solved?
E-68


E-61(B)

- Verify repair Go to Step 14

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-191
Step Action Value (s) Yes No
9
Using the DVM and check the TPS signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the TPS connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-68
V




Less than 1V
Go to Step 10
Repair faulty
harness and
verify repair
10
Using the DVM and check the TPS ground circuit.
1. Ignition "On", engine "Off".
2. Disconnect the TPS connector .
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-68
V




Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair
11

Using the DVM and check the TPS ground circuit.
Breaker box is available:
1. Ignition "Off", engine "Off".
2. Install the breaker box as type A. (ECM
disconnected).
Refer to 6E-95 page.
3. Disconnect the TPS connector.
4. Check the circuit for open circuit.
Was the problem found?
E-68

B39
Breaker Box

6E-204 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
5
Using the DVM and check the O2 sensor circuit for the
affected bank.
1. Ignition "On", engine "Off".
2. Disconnect the O2 sensor connector for the
affected bank.
3. Check the circuit for open, short to heater ground or
ground circuit.
Was the DVM indicated specified value?
E-77/E-78 BANK1/BANK2
V




Approximatly
450mV
Go to Step 7
Go to Step 6
6
Using the DVM and check the O2 sensor circuit for the
affected bank.
1. Ignition "On", engine "Off".
2. Disconnect the O2 sensor connector for the
affected cylinder.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specifed value?
E-77/E-78 BANK1/BANK2
VV





Less than 1V
Go to Step 15
Repair faulty
harness and
verify repair